Any way to make E38/E67 correct injector flowrate when in boost?

[MikeOD]

The LS9 and LSA operating systems seem to properly correct injector flowrate when they enter boost, but it seems all other E67 OS's, as well as I believe all E38 OS's stop correcting injector flowrate once they go above atmospheric pressure, and thus a fueling error gets built into the VVE and MAF tables...which can in a turbo car result in some funky fueling.

My solution to this point has been to run a return style fuel system with a 1:1 regulator and set the injector flowrate to the same value across the board, but if it's possible, on low boost setups where expected power is comparable to the LS9 and LSA engines, I'd like to somehow tell the ECM to properly follow the injector flow rate tables into boost.

Does anyone know the solution?

[joecar]

MAP-referenced FPR is preferred...

but, otherwise, edit the LS3/E38/E67 IFR table so that the squareroot flowrate-vs-pressure relationship extends down below 400 kPa (i.e. into the boost region).


[ i.e. 300 kPa is 1-bar boost, 400 kPa is BARO (NA WOT), 500 kPa is absolute vacuum (un-attainable) ]

[MikeOD]

Joe,

Do you mean B4001? If so, this table already covers from a 128 KPA delta to a 624 KPA delta, and the information in it is correct. The problem is that the once the MAP sensor actually goes above barometric pressure, the IFR continues to actually report and be calculated as the value at barometric pressure. The data is already there, the ECM isn't following it appropriately. I was wondering if there's possibly a max MAP KPA setting somewhere that the ECM looks at, and if the MAP reads above it, it defaults to the atmospheric value instead when it looks at the IFR table.

[joecar]

Hmmm, I see...

[ringram]

Sounds like a question for Ross..

[GMPX]

Or not :mrgreen:
I got no idea about fuel systems.

[izaks]

B8034

[MikeOD]

So if I set B8034 to the max that the MAP can actually read, then the injector flowrate will calculate properly when in boost? Awesome!!! Thank you.

[joecar]

Mike, can you post your tune file so I can have a look, thanks.